1. Bacterial Community Composition and Genes for Herbicide Degradation in a Stormwater Wetland Collecting Herbicide Runoff
- Author
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Stéphane Vuilleumier, Gwenaël Imfeld, Pierre-Yves Baccara, Florian Mauffrey, and Christelle Gruffaz
- Subjects
0301 basic medicine ,Environmental Engineering ,Stormwater ,Simazine ,Wetland ,010501 environmental sciences ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Environmental Chemistry ,0105 earth and related environmental sciences ,Water Science and Technology ,geography ,geography.geographical_feature_category ,Ecology ,Ecological Modeling ,Aquatic ecosystem ,food and beverages ,Pesticide ,Pollution ,030104 developmental biology ,chemistry ,Glyphosate ,Pesticide degradation ,Environmental science ,Surface runoff - Abstract
Stormwater wetlands collect and attenuate runoff-related herbicides, limiting their transport into aquatic ecosystems. Knowledge on wetland bacterial communities with respect to herbicide dissipation is scarce. Previous studies showed that hydrological and hydrochemical conditions, including pesticide removal capacity, may change from spring to summer in stormwater wetlands. We hypothesized that these changes alter bacterial communities, which, in turn, influence pesticide degradation capacities in stormwater wetland. Here, we report on bacterial community changes in a stormwater wetland exposed to pesticide runoff, and the occurrence of trz, atz, puh, and phn genes potentially involved in the biodegradation of simazine, diuron, and glyphosate. Based on T-RFLP analysis of amplified 16S rRNA genes, a response of bacterial communities to pesticide exposure was not detected. Changes in stormwater wetland bacterial community mainly followed seasonal variations in the wetland. Hydrological and hydrochemical fluctuations and vegetation development in the wetland presumably contributed to prevent detection of effects of pesticide exposure on overall bacterial community. End point PCR assays for trz, atz, phn, and puh genes associated with herbicide degradation were positive for several environmental samples, which suggest that microbial degradation contributes to pesticide dissipation. However, a correlation of corresponding genes with herbicide concentrations could not be detected. Overall, this study represents a first step to identify changes in bacterial community associated with the presence of pesticides and their degradation in stormwater wetland.
- Published
- 2017